1. Field of the Invention
The present invention relates to a reverse osmosis (RO) drain coupling and a method of installing the coupling in a drain pipe.
2. Description of the Prior Art
When an RO drinking water unit is to be added to an existing household water supply system, it is common practice to drain the reject water through a small drain line or tube emptying into the same drain pipe that drains the sink, washing machine or garbage disposer. This is a quick and relatively inexpensive procedure.
The RO drain tube has typically been connected to the drain pipe by a cylindrical two piece saddle clamp that fits over a hole drilled in the drain pipe. The drain tube fits within a tubular protuberance or inlet port of the saddle clamp that is aligned with the drain pipe hole. A resilient pad surrounds the internal end of the inlet port fitting to provide a fluid tight seal when the two halves of the clamp are tightened together.
Plumbing codes have now largely outlawed use of the saddle clamp arrangement, ostensibly because of problems associated with the drilling of a hole in the drain pipe.
As a consequence, various proposals have been advanced in the prior art to provide for emptying of the RO drain water into the drain pipe without having to drill a special hole.
One prior art method includes the step of cutting away a section of the usually rigid drain pipe and inserting a rigid plastic T-fitting in the resulting space. Compression nuts or the like are then fitted onto the drain line and the T-fitting to secure them together. This approach results in a more costly fitting and increased installation problems.
A tubular protuberance or port of the T-fitting receives the RO drain tubing so that RO drain water does not empty into the drain pipe through a drilled hole, but instead empties into the T-fitting which discharges into the drain pipe.